TWI612722B - Lte multiband monopole antenna used in electronic appliance having metal frame - Google Patents

Abstract

The invention relates to an LTE multi-frequency monopole antenna applied to an electronic device with a metal frame, comprising a grounding element, an antenna element and a metal frame part; the grounding element is located on the first surface of the substrate, and the antenna element is located on the opposite substrate a second surface of a surface, the metal frame portion is located at a periphery of the substrate; the antenna element includes a first radiating unit and a second radiating unit, the first radiating unit is connected to a circuit component group, and the antenna signal is fed by the first radiating unit, and the second The radiating unit is extended by the grounding member, one end of which is connected to a first L-shaped metal portion perpendicular to the metal frame portion, and the other end of the second radiating unit is connected to the C-shaped extending portion by an inductive element. The antenna of the present invention has a return loss of less than 6 dB, operates at a low frequency operating bandwidth of 273 MHz (687-960 MHz), has an average gain of 0.8 dB (0.2-1.4 dBi), and an average efficiency of approximately 46.75% (42-53). %); the high frequency operating bandwidth is 1021 MHz (1675-2696 MHz), the average gain is 3.78 dB (3.4-4.3 dBi), and the average efficiency is 77.56% (70-85%). The antenna of the present invention can be applied to LTE700/ Bands for GSM850/900 (704-960 MHz) and GSM1800/1900/UMTS/LTE2300/2500 (1710-2690 MHz).

Description

LTE multi-frequency monopole antenna for electronic devices with metal frame

The present invention relates to a monopole antenna, and more particularly to an LTE multi-frequency monopole antenna applied to an electronic device having a metal frame.

With the rapid development of the mobile communication industry, today's wireless transmission interface has gradually evolved from the third generation (3G) mobile communication system to the fourth generation (4G) mobile communication system, and Long Term Evolution (LTE) is the first One of the communication protocols in the four-generation mobile communication system.

The demand for mobile communication devices is becoming more and more diversified. In order to meet the needs of users, more components are placed in mobile communication devices, but this will inevitably be compressed into the design space of the antenna.

In particular, in recent years, the display screen of the mobile communication device has moved toward a large size, so that the area between the display screen and the top and bottom edges of the mobile communication device casing is very narrow, usually less than 10 mm, and the mobile communication device The antenna is designed in this area.

Therefore, the antenna designer must not only consider the requirements of the antenna performance, but also the antenna should be small-sized as the main axis, integrated with the surrounding environment, and can achieve broadband frequency band operation; and the antenna is reduced in direction to reduce the height of the antenna. Important, so an antenna height of at least 10 mm is the current trend in antenna design for mobile communication devices.

In addition, most of the casings of the previous mobile communication devices were made of plastic materials. As the mobile communication device was also thinner, the mechanical strength of the casing made of plastic material was insufficient, so the mobile communication device was changed to metal. The material is used as the material of the back cover or the frame of the mobile communication device to improve the mechanical strength of the mobile communication device, and even the metal back cover or the frame can make the appearance of the mobile communication device beautiful and improve the overall texture, especially It is a high specification mobile communication device.

The use of a metal back cover or a framed mobile communication device can increase the mechanical strength of the mobile communication device, but the antenna design environment is more difficult. Therefore, the mobile communication device displays the screen and the metal frame. It is currently a challenge to design an antenna that satisfies the multi-band antenna of the LTE system and has good radiation characteristics under the available area.

<Citations>

Document 1: US 8547283 B2

Document 2: US 20110095949 A1

Document 3: TW I488361

Document 4: TW I509883

Document 5: JH Lu and JL Guo, "Small-Size Octaband Monopole Antenna in an LTE/WWAN Mobile Phone," IEEE Antennas and Wireless Propag. Lett. , vol. 13, pp. 548-551, 2014.

Document 6: SC Chen and KL Wong, "Small-Size Wideband Chip Antenna For WWAN/LTE Operation and Close Integration with Nearby Conducting Elements in the Mobile Handset," Microwave Opt. Technol. Lett. , vol.53, no.9, Pp.1998-2004, Sep. 2011.

Document 7: SC Chen and KL Wong, “Wideband Monopole Antenna Coupled with a Chip-Inductor-loaded Shorted Strip for LTE/WWAN Mobile Handset,” Microwave Opt. Technol. Lett. , vol.53, no.6, pp.1293 -1298, Jun. 2011.

In the above documents, some disclose the use of a three-dimensional structure, or have the disadvantage of having a large antenna area, and there is still room for improvement. Moreover, the above-mentioned documents do not consider the back cover or the frame of the metal material in the antenna design. In practical applications, the antenna characteristics will be greatly affected.

The main object of the present invention is to provide an antenna, particularly for use in a mobile communication device having a metal frame, which is mainly disposed in a limited space and can achieve multi-band operation to meet the needs of a mobile communication device.

The object and effect of the present invention are achieved by the following techniques:

An LTE multi-frequency monopole antenna applied to an electronic device having a metal frame; comprising at least one grounding element, an antenna element and a metal frame portion;

The grounding element is located on a first surface of a substrate, and the antenna element is disposed on a second surface of the substrate opposite to the first surface, the metal frame portion is located at a periphery of the substrate;

The antenna element includes a first radiating element and a second radiating unit; the first radiating unit includes a circuit component group extending from each other and an L-shaped extension, the L-shaped extension being remote from the circuit component group One end is a first free end; the circuit component group includes a first inductive component and a capacitive component, one end of the capacitive component is an antenna signal feed point and is connected to the ground component, and the other end of the capacitive component Connecting the first inductive component and the L-shaped extension, and connecting the other end of the inductive component to the grounding component;

The second ejector unit is coupled to the grounding element and has at least a C-shaped extension and a hook-shaped extension, the C-shaped extension and the hook-shaped extension having a third free end and a fourth free end, respectively a second inductive component is connected between the C-shaped extension and the hook-shaped extension, and the hook-shaped extension is provided with an end point connected to the grounding element, and an end point of the hook-shaped extension Forming an opening between the fourth free ends, applied to an LTE multi-frequency monopole antenna having a metal frame electronic device, wherein the L-shaped extension portion penetrates the hook-shaped extension portion from the opening, and the hook-shaped extension portion The end is connected to the metal frame portion, and the free end of the C-shaped extension is tied to a side of the junction of the second radiation unit and the ground element;

The metal frame portion includes a first L-shaped metal portion, a second L-shaped metal portion, and a U-shaped metal portion, the first L-shaped metal portion, the second L-shaped metal portion, and the U-shaped metal portion The surround is disposed around the substrate.

An LTE multi-frequency monopole antenna applied to an electronic device having a metal frame as described above, wherein the second radiating element is from a terminal connected to the ground element to a path of the fourth free end, and then A second free end of the first L-shaped metal portion is coupled to excite the first mode.

An LTE multi-frequency monopole antenna applied to an electronic device having a metal frame as described above, wherein the second radiating element extends from an end point connected to the ground element to a third freedom of the C-shaped extension The path of the end to excite the second mode.

The LTE multi-frequency monopole antenna applied to an electronic device having a metal frame as described above, wherein the feeding point to the first inductive element connects the path of the ground element to excite the third mode.

An LTE multi-frequency monopole antenna applied to an electronic device having a metal frame as described above, wherein the second radiating element extends from a path of an end of the ground element to a path of a fourth free end and then via the connection A second free end of the first L-shaped metal portion excites a fourth mode, the fourth mode having a frequency that is three times the frequency of the first mode.

An LTE multi-frequency monopole antenna applied to an electronic device having a metal frame as described above, wherein the second radiating element extends from an end of the ground element to a third free end of the C-shaped extension The path is to excite a fifth mode, the fifth mode having a frequency that is three times the frequency of the first mode.

An LTE multi-frequency monopole antenna applied to an electronic device having a metal frame as described above, wherein a path from the feed point to the first free end excites a sixth mode.

An LTE multi-frequency monopole antenna applied to an electronic device having a metal frame as described above, wherein the first mode, the second mode, and the third mode collectively cover a band of 687 MHz to 960 MHz The fourth mode, the fifth mode, and the sixth mode collectively cover the 1675 MHz to 2696 MHz band.

An LTE multi-frequency monopole antenna applied to an electronic device having a metal frame as described above, wherein the first L-shaped metal portion corresponds to the second L-shaped metal portion, and the two ends of the U-shaped metal portion Forming a first pitch and a second pitch respectively adjacent to the first L-shaped metal portion and the second L-shaped metal portion, wherein the first pitch and the second pitch are equal, the first L A third spacing is formed between the shaped metal portion and the second L-shaped metal portion.

The antenna of this creation covers the band 687 MHz to 960 MHz for its first mode, second mode and third mode; the fourth mode, the fifth mode and the sixth mode together cover 1675 MHz to 2696 MHz. The frequency band is therefore applicable to the antenna device of the mobile communication device; in addition, the antenna area of the present invention is approximately 30 × 8 mm ² , which is the antenna area of the present invention compared to the prior art which currently covers the above eight frequency bands. Can be reduced by more than 20%.

In view of the above, the LTE multi-frequency monopole antenna of the present invention applied to an electronic device having a metal frame has the following advantages:

1. The antenna can be designed by the first radiating element and the second radiating element, and the area required for the antenna can be reduced in the same frequency band as the previously published related documents to meet the requirements of the mobile communication device.

2. The antenna element is combined with the antenna element by the metal frame portion of the electronic device, and the metal frame portion is incorporated into one of the antenna radiators, so that the environment around the antenna of the mobile communication device can be effectively integrated.

3. This antenna is based on the experimental measurements of the examples, and it is known that good radiation characteristics can be maintained in a wide operating band.

For a more complete and clear disclosure of the technical content, the purpose of the invention and the effects thereof achieved by the present invention, it is explained in detail below, and please refer to the drawings and drawings:

Please refer to the first and second figures for revealing a preferred embodiment of the LTE multi-frequency monopole antenna applied to an electronic device having a metal frame, the antenna comprising at least a grounding component (1) and an antenna component (2) , metal frame part (3); where:

The grounding element (1) is disposed on the first surface (41) of the substrate (4), the substrate (4) further comprising a second surface (42) opposite to the first surface (41) on the second surface (42) A clearance area (421) is formed on the upper right side.

The antenna element (2) is disposed on the second surface (42) of the substrate (4) by printing, etching, sheet metal stamping or cutting, and is a clearance area (421) on the second surface (42).

The antenna element (2) includes at least a first radiating element (21) and a second radiating element (22) disposed on the first surface (41) of the substrate (4).

The first radiating element (21) includes a circuit component group (211), an L-shaped extension (212) feed point (A), and a first free end (D), wherein the circuit component group (211) includes the first inductance component (L1) and the capacitive element (C1), the feed point (A) is electrically connected to the ground element (1) and the capacitor element C1 is connected in series, and then the first inductance element (L1) is connected in parallel, and the other end point of the first inductance element (L1) (B) Connecting the grounding element (1); the capacitive element C1 and the first inductive component (L1) form a high-pass matching circuit.

The second radiating element (22) extends from the grounding element (1) via a joint (C), and the second radiating element (22) has at least a hook-like extension (221) and a C-shaped extension (222). The second inductive element (L2) is connected between the hook extension (221) and the C-shaped extension (222).

The metal frame portion (3) is composed of a first L-shaped metal portion (31) perpendicular to the substrate (4), a second L-shaped metal portion (32) and a U-shaped metal portion (33), wherein the first L-shaped metal portion The portion (31) is connected to the end of the hook-like extension (221) of the second radiating element (22), and the second L-shaped metal portion (32) and the U-shaped metal portion (33) are connected to the grounding member (1), and The first L-shaped metal portion (31) has a spacing W between the second L-shaped metal portion (32), and the first L-shaped metal portion (31) and the U-shaped metal portion (33) have a spacing d1, and a second The L-shaped metal portion (32) and the U-shaped metal portion (33) have a spacing d2, wherein the spacing d1 is equal to the spacing d2.

In addition, one end of the L-shaped extension (212) of the first radiating element (21) away from the feeding point (A) is a first free end (D); a hook-shaped extension of the second radiating element (22) (221) The ends of the C-shaped extensions (222) are respectively a fourth free end (H) and a third free end (F); the end of the first L-shaped metal portion (31) away from the hook-shaped extension (221) is Second free end (E). Wherein, the feeding point (A) to the first free end (D) form a feeding path unipolar path (AD), and the contact point (C) to the second free end (E) form a long path (CE) of a parasitic short circuit, The short path (CF) of the parasitic short circuit is formed from the contact point (C) to the third free end (F); the resonance mode is mainly generated by the long path (CE) of the parasitic short circuit and the short path (CF) of the parasitic short circuit in the low frequency part State, then add the feed point (A) covered by the high-pass matching circuit composed of the capacitive element C1 and the first inductance element (L1); the high-frequency part is the long path (CE) of the parasitic short circuit and the parasitic short circuit The short-path (CF) multiplier covers its operating frequency band; as for the feed-in unipolar path (AD), the coupling amount required for other paths is provided to adjust the impedance matching; the short path (CF) tail for the parasitic short circuit There is a spacing (G) between the end and the boundary of the clearance area (421).

The actual fabrication of the monopole antenna embodiment is further experimentally measured and theoretically simulated for the surface current, structure, and path parameters of the monopole antenna. Table 1 discloses the optimum path parameter values of the monopole antenna of the present invention.

Table 3.1 Optimal path parameter values of the monopole antenna of the present invention         <TABLE border="1" borderColor="#000000" width="85%"><TBODY><tr><td> Parameters</td><td> L₁</td> <td> L₂</td><td> C₁</td><td> G </td></tr><tr><td> Design value </td><td> 8.2 nH </td><td> 10 nH </td><td> 3.3 pF </td><td> 0.5 mm </td></tr></TBODY> </TABLE>

The preferred embodiment of the antenna selects the following dimensions 來 for experimental measurement results and theoretical simulation results: the area of the ground element (1) is approximately 120 × 65 mm ² , and the area of the antenna element (2) is 30 × 8 mm ² ; the substrate (4) is made of a glass fiber dielectric substrate with a thickness of 0.8 mm (dielectric coefficient is about 4.4), and the antenna element (2) is made of copper with a thickness of 0.02 mm, the first L-shaped metal portion (31), The metal frame composed of the second L-shaped metal portion (32) and the U-shaped metal portion (33) is made of a copper sheet having a thickness of 0.2 mm.

The path from the feed point (A) to the first free end (D) is about 29.2 mm; the path from the contact C through the fourth free end (H) to the second free end (E) is about 62.1 mm, forming a parasitic The long path of the short circuit; the path from the junction C to the third free end (F) is about 47.5 mm, forming a short path of parasitic short circuit.

Please refer to the third figure for the return loss diagram of the preferred embodiment of the LTE multi-frequency metal frame monopole antenna. The vertical axis is the return loss value in dB; the horizontal axis is the operating frequency in MHz. . Among them, the solid line is the theoretical simulation result, and the solid line has the dot as the experimental measurement result. As can be seen from the third figure, the present invention has a reflection loss value greater than 6 dB as a standard, and the low frequency portion of the operating frequency range is 687-960 MHz, and the low frequency operation bandwidth is 273 MHz, and the bandwidth percentage is about 33.1%; The high frequency part is between 1675 and 2696 MHz, the high frequency operation bandwidth is 1021 MHz, and the bandwidth percentage is about 46.7 %. The monopole antenna of the present invention can satisfy LTE700/GSM850/900 (704 MHz to 960 MHz) and GSM1800/ Frequency operation requirements for 1900/UMTS/LTE2300/2500 (1710 MHz to 2690 MHz).

In the preferred embodiment of the antenna, the transmitting and receiving antenna signals have three transmission paths, and correspondingly generate five excitation modes, and a mode excited by the first inductance element (L1):

First, the first excitation mode is 725 MHz: excited by the long path (CE) of the parasitic short circuit;

Second, the second excitation mode 809 MHz: excited by a short path (CF) of the parasitic short circuit;

Third, the third excitation mode 906 MHz: is excited by the feeding point (A) through the path of the first inductive component (L1) to the end point B connected to the grounding component (1);

Fourth, the fourth excitation mode 2031 MHz: the path is the same as the first excitation mode, which is three times the frequency of the first excitation mode;

5. The fifth excitation mode is 2334 MHz: the path is the same as the second excitation mode, which is three times the frequency of the second excitation mode;

Sixth, sixth excitation mode 2600 MHz: excited by the feedthrough unipolar path (AD).

The fourth figure shows a simulated reflection loss diagram of the monopole antenna structure of the present invention. Antenna-1 is a long path (CE) without parasitic short circuit. It can be found that the low-band impedance bandwidth is not enough to cover the low-frequency operating band. It can be known that the long path (CE) of the parasitic short circuit can be in the low-frequency resonance mode. The contribution of the low-band impedance bandwidth is also affected, and the high-band partial impedance bandwidth is also affected. Because the high-frequency band has the multiplier contribution impedance bandwidth of this mode, the resonance mode proof of the structure of the input impedance diagram is discussed later. Antenna-2 is a short path (CF) without parasitic short circuit. The low-band impedance matching is only about 4 dB. It can be proved that the short path (CF) of the parasitic short circuit can resonate at another mode in the low frequency and contribute the low-band impedance bandwidth. The mode of the high frequency band of about 2550 MHz is also contributed by this path. Antenna-3 is not added to the LC high-pass matching circuit. It is found that this matching circuit has a large contribution to the impedance bandwidth of the low frequency band, and the impact on the high frequency band is small. First, refer to the fifth picture for the Antenna-1 analog input. Impedance map, as shown in the fifth (a) frequency response diagram, the long path (CE) of the parasitic short circuit can be approximately 700 MHz resonant main mode and 2100 MHz resonant multiplication mode, observe the fifth figure (b) and ( c) Smith chart, Antenna-1 has a resonance mode in the low frequency operation band, but the input impedance is not matched; the high frequency part has two resonance modes, and then the sixth picture Antenna-2 analog input impedance diagram Figure 6 (a) Frequency response, the short path (CF) of the parasitic short circuit can be approximately 850 MHz resonant main mode and 2550 MHz resonant multiplication mode, observe the sixth figure (b) and (c) Smith chart, Antenna-2 has a parasitic short path (CE) in the low frequency band and a resonant mode of the LC high-pass matching circuit, but the modal input impedance distribution is not yet in the range of VSWR=3. Finally, refer to the seventh figure Antenna-3. Analog input impedance map, Figure 7 (a) Frequency response can prove LC high-pass matching The path can be at 1200 MHz, mainly because the ground can be grounded from the feed point (A) via the first inductive component (L1) to a high-impedance mode at low frequencies, whereby the low-band real impedance can be boosted by the modality. The feed point (A) is connected in series with a capacitive element C1 to adjust the low-band imaginary impedance to achieve impedance matching. Observe the seventh figure (b) and (c) Smith chart, Proposed and Antenna-3, Antenna-3 The low-band portion is indeed a capacitive input impedance distribution, and the high-frequency band does not change much, which proves the effect of the LC high-pass matching circuit on the antenna input impedance.

The parameters will be discussed and analyzed for Proposed Antenna. First fixed parameters: L ₂ = 10 nH, C ₁ = 3.3 pF, G = 0.5 mm, and the parameter L ₁ is the first inductance component (L1) of the high-pass matching circuit, as shown in the eighth figure parameter L ₁ reflection loss variation diagram, When the parameter L ₁ changes from 7.2 nH to 9.2 nH, since L ₁ is a high-pass matching circuit component, the amount of inductance mainly affects the impedance bandwidth of the low frequency, which also confirms that the high-pass matching circuit described above mainly controls the low-band portion. Then fixed parameters: L ₁ = 8.2 nH, C ₁ = 3.3 pF, G = 0.5 mm, and the parameter L ₂ is the second inductance element (L2) in the short path (CF) of the parasitic short circuit, as shown in the ninth parameter L ₂ reflection loss variation map, when the parameter L ₂ changes from 8 nH to 12 nH, it can be observed that the frequency of the second mode of the low frequency band will obviously move to the low frequency, and the short path of the parasitic short circuit (CF) is added by the second inductance. The component (L2) has to shorten the resonance wavelength and can resonate in the low frequency band with a shorter path, but the inductance should not be too large, otherwise the radiation efficiency of the antenna will be affected. Fixed parameters: L ₁ = 8.2 nH, L ₂ = 10 nH, G = 0.5 mm. Exploring parameter C ₁ is the capacitive element C1 of the high-pass matching circuit, as shown in the tenth parameter C ₁ reflection loss change diagram, when the parameter C ₁ is 1.3 pF changes to 5.3 pF, because the capacitive component C1 is placed in the feedband unipolar path (AD), it will affect the imaginary impedance of the overall antenna, which has a strong impact on the impedance bandwidth. The last fixed parameter: L ₁ = 8.2 nH, L ₂ = 10 nH, C ₁ = 3.3 pF, and the parameter G is the distance between the short path (CF) end of the parasitic short circuit and the boundary of the clearance area (421) (G) , as shown in the eleventh figure, the parameter G reflection loss change graph, when the parameter G changes from 0.8 mm to 0.2 mm, the short-path (CF) of the parasitic short-circuit is also the low-band second mode and the multi-frequency multi-band The two modes have an effect, and this phenomenon is very reasonable.

The current surface profile is used to determine the path of the modality, and the physical characteristics of the monopole antenna of the present invention are illustrated, as shown in Fig. 12 (a), (b), (c), (d), (e). The monopole antenna of the present invention simulates a current map. The following describes the current distribution of the analog monopole antenna at frequencies of 715 MHz, 778 MHz, 859 MHz, 1881 MHz, and 2562 MHz. The above frequencies are the frequency points matched by the input impedance mode, and the resonance of the mode is known. Path length. Referring first to Figure 12(a), when the frequency is 715 MHz, a strong current distribution is observed on the long path (CE) of the parasitic short circuit, which is consistent with the quarter-wavelength of the monopole antenna. To the weak current distribution, the total path length is 67.7 mm (approximately 0.16λ), because the resonance path is shortened due to the coupling effect between the small-sized antenna paths, resulting in a resonance length of less than a quarter wavelength, which can be proved by the above results. The mode at 715 MHz is the dominant mode of resonance by the long path (CE) of the parasitic short circuit; as shown in Fig. 12(b), when the frequency is 778 MHz, the strong current distribution is concentrated on the parasitic short circuit. On the short path (CF), the modal resonant path length can be shortened by adding a second inductive component (L2) in the short path (CF) of the parasitic short circuit, and the total path length is 47.5 mm (about 0.12λ). From the above results, it can be proved that the mode at the frequency of 778 MHz is the main mode of resonance by the short path (CF) of the parasitic short circuit; as shown in the twelfth figure (c), when the frequency is 859 MHz, the comparison can be observed. The strong current distribution is concentrated on the first inductive component (L1) in the high-pass matching circuit. As a result, it can be proved that the first inductance element (L1) is modal after being grounded at a frequency of 859 MHz; in the twelfth diagram (d), when the frequency is 1881 MHz, the modal is a long path of parasitic short circuit. (CE) The frequency doubling mode of resonance, the strong current distribution is concentrated on the long path (CE) of the parasitic short circuit, and there is a reverse current zero point in the current distribution, and the total path length is 67.7 mm (about 0.43λ); Finally, as shown in the twelfth figure (e), when the frequency is 2562 MHz, since this mode is the frequency doubling mode of the short path (CF) of the parasitic short circuit, it can be observed that The strong current distribution is concentrated on the short path (CF) of the parasitic short circuit. There is also a reverse current zero point in the current distribution. It is also the physical effect of the frequency doubling mode. The total path length is 47.5 mm (about 0.4λ).

As shown in Figures 13(a)-(e), the simulated and measured 2D radiation pattern of a monopole antenna of the present invention at center frequencies of 740 MHz, 925 MHz, 1795 MHz, 2045 MHz, and 2500 MHz Five center frequencies are observed in the center frequency of the eight operating bands, the low-band center frequencies are 740 MHz and 925 MHz, the high-band center frequencies are 1795 MHz, 2045 MHz and 2500 MHz, and the low-frequency part XY plane has a typical monopole antenna. Omnidirectional radiation field type, and there are many field zeros on the high frequency part field. It can be seen that if the antenna operating wavelength is smaller than the system ground plane size (ie, the higher the operating frequency), the antenna is on the ground plane surface. The current zero point is relatively more, and the radiation field type has relatively more concave zero points. In addition, it is also found that the radiation field type is not completely symmetrical, because the antenna element (2) is placed in position relative to the whole grounding element. (1) The clearance area (421) on the right side above the second surface (42), the antenna body is also asymmetric, so that the result of the asymmetric radiation pattern is obtained.

Figure 14 is a diagram showing the simulated and measured gain of the monopole antenna of the present invention. The fifteenth figure is a simulation diagram of the simulated and measured radiation efficiency of the monopole antenna of the present invention. It can be observed from the fourteenth and fifteenth views that the preferred embodiment of the present antenna operates in the low frequency LTE700/GSM850/900 frequency band, and the antenna gain is between 0.2 and 1.4 dBi, and the antenna efficiency is about 42-53%. When operating at high frequency GSM1800/1900/UMTS/LTE2300/2500, the antenna gain is between 3.4-4.3 dBi and the antenna efficiency is about 70-85%. The performance of the monopole antenna design of the present invention has been adapted to practical applications. Claim.

The above is only a part of the embodiments of the present invention, and is not intended to limit the present invention. It is intended to be included in the scope of the present invention.

In summary, the embodiments of the present invention can achieve the expected use efficiency, and the specific technical means disclosed therein have not been seen in similar products, nor have they been disclosed before the application, and have completely complied with the patent law. The regulations and requirements, the application for invention patents in accordance with the law, and the application for review, and the grant of patents, are truly sensible.

(1)‧‧‧ Grounding components

(2) ‧‧‧Antenna components

(21)‧‧‧First Radiation Unit

(211)‧‧‧Circuit component group

(212) ‧‧‧L-shaped extension

(22) ‧‧‧second radiating element

(221)‧‧‧Hook extension

(222)‧‧‧C-shaped extension

(3)‧‧‧Metal frame department

(31)‧‧‧First L-shaped metal parts

(32)‧‧‧Second L-shaped metal parts

(33)‧‧‧U-shaped metal parts

(4) ‧‧‧Substrate

(41) ‧‧‧ first surface

(42) ‧‧‧second surface

(421)‧‧‧ clearance area

(A) ‧ ‧ feed points

(B) ‧‧‧ endpoint

(C) ‧ ‧ endpoints

(E) ‧ ‧ second free end

(D) ‧ ‧ first free end

(F) ‧ ‧ third free end

(G) ‧‧‧ spacing

(H) ‧ ‧ fourth free end

(L1)‧‧‧First Inductive Component

(L2)‧‧‧second inductance component

(C1)‧‧‧Capacitive components

(AD)‧‧‧Feed with unipolar path

(CE) ‧‧‧Long path of parasitic short circuit

(CF) ‧‧‧ Short path of parasitic short circuit

First: Schematic diagram of the structure of an LTE multi-frequency monopole antenna applied to an electronic device having a metal frame according to the present invention

FIG. 2 is a partially enlarged schematic view showing the structure of an LTE multi-frequency monopole antenna applied to an electronic device having a metal frame according to the present invention;

The third figure: the single pole antenna structure simulation and actual measurement reflection loss map of the present invention

Figure 4: Simulated reflection loss diagram of the monopole antenna structure of the present invention

Figure 5: Analog input impedance map for Antenna-1; (a) frequency response map; (b) and (c) Smith chart

Figure 6: Analog input impedance map for Antenna-2; (a) frequency response map; (b) and (c) Smith chart

Figure 7: Antenna-3 analog input impedance map; (a) frequency response map; (b) and (c) Smith chart

Figure 8: Parameter L ₁ reflection loss change diagram

Figure IX: Parameter L ₂ reflection loss change diagram

Figure 10: Parameter C ₁ reflection loss change graph

Figure 11: Parameter G reflection loss change diagram

Twelfth Figure (a): Simulated current diagram of the monopole antenna of the present invention at a frequency of 715 MHz

Twelfth Figure (b): Simulated current diagram of the monopole antenna of the present invention when the frequency is 778 MHz

Twelfth Figure (c): Simulated current diagram of the monopole antenna of the present invention when the frequency is 859 MHz

Twelfth Figure (d): Simulated current diagram of the monopole antenna of the present invention when the frequency is 1881 MHz

Twelfth Figure (e): When the frequency twelfth figure of the present invention is an analog current diagram of a monopole antenna of 2562 MHz, the monopole antenna analog current diagram of the present invention

Thirteenth Figure (a): Simulated and measured 2D radiation pattern of a monopole antenna of the present invention at a center frequency of 740 MHz

Thirteenth Figure (b): Simulated and measured 2D radiation pattern of a monopole antenna of the present invention at a center frequency of 925 MHz

Thirteenth Figure (c): Simulated and measured 2D radiation pattern of a monopole antenna of the present invention at a center frequency of 1795 MHz

Thirteenth (d): Simulated and measured 2D radiation pattern of a monopole antenna of the present invention at a center frequency of 2045 MHz

Thirteenth (e): Simulated and measured 2D radiation pattern of a monopole antenna of the present invention at a center frequency of 2500 MHz

Figure 14: Simulation and measured gain diagram of the monopole antenna of the present invention

Figure 15: Simulation and measured radiation efficiency diagram of the monopole antenna of the present invention

(2) ‧‧‧Antenna components

(21)‧‧‧First Radiation Unit

(22) ‧‧‧second radiating element

(3)‧‧‧Metal frame department

(31)‧‧‧First L-shaped metal parts

(32)‧‧‧Second L-shaped metal parts

(33)‧‧‧U-shaped metal parts

(4) ‧‧‧Substrate

(41) ‧‧‧ first surface

(42) ‧‧‧second surface

(421)‧‧‧ clearance area

Claims (9)

An LTE multi-frequency monopole antenna applied to an electronic device having a metal frame; comprising at least one grounding element, an antenna element and a metal frame portion; the grounding element is located on a first surface of a substrate opposite to the first surface The antenna element is disposed on a second surface of the substrate, the metal frame portion is located at a periphery of the substrate; the antenna element includes a first radiating unit and a second radiating unit; and the first radiating unit includes each other Connecting a circuit element group and an L-shaped extension portion, wherein an end of the L-shaped extension away from the circuit component group is a first free end; the circuit component group includes a first inductance component and a capacitance component, One end of the capacitive element is an antenna signal feed point and is connected to the ground element, and the other end of the capacitive element is connected to the first inductance element and the L-shaped extension, and the other end of the inductance element is connected The grounding element; the second ejector unit is coupled to the grounding element and has at least a C-shaped extension and a hook-shaped extension, the C-shaped extension And the hook-shaped extensions respectively have a third free end and a fourth free end, and the second inductive element is connected between the C-shaped extension and the hook-shaped extension, and the hook-shaped extension has an end point Connecting with the grounding element, an opening is formed between an end of the hook-shaped extension and the fourth free end, and the L-shaped extension is applied to an LTE multi-frequency monopole antenna having an electronic device with a metal frame The opening extends deep into the hook-shaped extension, the end of the hook-shaped extension is connected to the metal frame portion, and the free end of the C-shaped extension is tied to the second radiation unit and the ground element a side of the joint; the metal frame portion includes a first L-shaped metal portion, a second L-shaped metal portion, and a U-shaped metal portion, the first L-shaped metal portion, the second L-shaped metal portion, and The U-shaped metal portion is surrounded by the substrate. An LTE multi-frequency monopole antenna for use in an electronic device having a metal frame as described in claim 1, wherein the second radiating element is from an end point connected to the ground element to the fourth free The end path is further excited by the second free end of the connected first L-shaped metal portion to excite the first mode. An LTE multi-frequency monopole antenna for use in an electronic device having a metal frame as described in claim 2, wherein the second radiating element extends from an end point connected to the ground element to the C-shape A path of the third free end of the extension to excite the second mode. An LTE multi-frequency monopole antenna for use in an electronic device having a metal frame as described in claim 3, wherein the feeding point to the path of the first inductive element connecting the ground element to excite a third Modal. An LTE multi-frequency monopole antenna for use in an electronic device having a metal frame as described in claim 4, wherein the second radiating element extends from an end of the ground element to a path of the fourth free end And passing through the second free end of the connected first L-shaped metal portion to excite a fourth mode, the fourth mode having a frequency that is three times the frequency of the first mode. An LTE multi-frequency monopole antenna for use in an electronic device having a metal frame as described in claim 5, wherein the second radiating element extends from an end of the ground element to the C-shaped extension The third free end path elicits a fifth mode, the fifth mode having a frequency that is three times the frequency of the first mode. An LTE multi-frequency monopole antenna for use in an electronic device having a metal frame as described in claim 6, wherein a path from the feed point to the first free end is used to excite a sixth mode . An LTE multi-frequency monopole antenna for use in an electronic device having a metal frame as described in claim 7, wherein the first mode, the second mode, and the third mode together In the 687 MHz to 960 MHz band, the fourth mode, the fifth mode, and the sixth mode collectively cover the 1675 MHz to 2696 MHz band. An LTE multi-frequency monopole antenna applied to an electronic device having a metal frame according to any one of claims 1 to 8, wherein the first L-shaped metal portion and the second L-shaped metal Correspondingly, the two ends of the U-shaped metal portion are respectively adjacent to the first L-shaped metal portion and the second L-shaped metal portion and each form a first pitch and a second pitch, and the first spacing The second pitch distance is equal, and a third pitch is formed between the first L-shaped metal portion and the second L-shaped metal portion.